No sound or the music output is muted

In the recent version of Voyage MuBox, there is a known issue that the music output is muted after reboot. Run the following commands to check if you music device is set to mute:

# amixer

Simple mixer control 'XMOS Clock Selector',0
  Capabilities: pvolume pswitch penum
  Playback channels: Front Left - Front Right
  Limits: Playback 0 - 127
  Mono:
  Front Left: Playback 127 [100%] [0.00dB] [off] 
  Front Right: Playback 127 [100%] [0.00dB] [off]
Simple mixer control 'XMOS Clock Selector',1                                
  Capabilities: pvolume pvolume-joined pswitch pswitch-joined penum
  Playback channels: Mono
  Limits: Playback 0 - 127
  Mono: Playback 127 [100%] [0.00dB] [off]

(Note: you may use command amixer -c 1 if you have USB DAC, where -c 1 specifies 2nd sound device. Use command cat /proc/asound/cards or aplay -l to list all sound devices detected)

If you see the Playback is set to [off], the music output is muted. You can use alsamixer tools to unmute (by press ‘M’ key to toggle mute/unmute for each control). Or you can simply run the following commands:
(Note: may need to pass -c 1 after amixer command to specify 2nd sound device, e.g. USB DAC):

# amixer scontrols|sed -e 's/^Simple mixer control//'|while read line;do amixer sset "$line" unmute;done                             

Simple mixer control 'XMOS Clock Selector',0
  Capabilities: pvolume pswitch penum
  Playback channels: Front Left - Front Right
  Limits: Playback 0 - 127
  Mono:
  Front Left: Playback 127 [100%] [0.00dB] [on]
  Front Right: Playback 127 [100%] [0.00dB] [on]
Simple mixer control 'XMOS Clock Selector',1
  Capabilities: pvolume pvolume-joined pswitch pswitch-joined penum
  Playback channels: Mono
  Limits: Playback 0 - 127
  Mono: Playback 127 [100%] [0.00dB] [on]